1. Field of the Invention
The present invention relates to an inspection apparatus that performs a process for performing surface inspection of an inspection target, and a method thereof.
2. Description of the Related Art
Conventionally, there is an inspection apparatus which detects a surface shape of an object to be inspected by irradiating a surface of the object with illumination light and detecting reflected light from the object.
In general, surface shapes of an object to be inspected differ according to manufacturing processes. In a case where a plurality of types of surface shape is to be detected, it is necessary to provide a plurality of inspection apparatuses that correspond to the surface shapes. Otherwise, a plurality of detection units needs to be included in one inspection apparatus.
Japanese Patent Application Laid-Open No. 06-222013 discusses an inspection apparatus including three types of illumination unit and two types of imaging unit. The inspection apparatus discussed in Japanese Patent Application Laid-Open No. 06-222013 detects three types of surface shape, i.e., scratch, stain, and bulge that appear on the surface of an object to be inspected, by switching operations between the three types of illumination unit and between the two types of imaging unit.
The inspection apparatus discussed in Japanese Patent Application Laid-Open No. 06-222013 changes image capturing conditions, acquires a plurality of images, and performs surface inspection to detect a plurality of types of surface shapes. Therefore, it is necessary to acquire a plurality of images under a plurality of imaging conditions according to a conventional technique, which makes the surface inspection process complex.